Improvement in stop-valves



NPETERS. PHOTO-LITHOGRAPHER, WASHINGTON. DV

anatomia.

BENJAMIN GREEN MAlirrI'N, OE NEW YORK, N. "Y.

i Letters Patent No. 89,781, dated May 4, 1869.

\ `IICLIIIRQVEIMENT IN STOP-VALVES.`

The Schedule referred to inthese Letters Patent andv making vpart ofthe same.

To all whom it 'ma/y concern.-

' sectionof a steam-valve, constructed according to my improvement Y y This invention consists in a valve-plug of novel construction, whereby a simple and efficient steam-valve is obtained. v A AReferring to the accompanying drawings- A represents the outer box, having `the usual induction and eduction-passages, and an upwardly-ex'-v tending central chamber, E, of square or quadrilatera'l formV in its transverse section," and having, also, formed in it, an inclined valve-seat, a, arranged across the inletfpassage. w l l Arranged so as to close upon the inclined seat q. is a vertically-sliding valve-plug, B B'. y

Said valve-plug is fitted to slide within the chamber E,land it consists of aloose face, or'valve-plate B, and a wedge, B; is square, or quadrilateral in its trans- Vverse s ection,-and is supported by athreaded stem, b, which Hfits and works in` a female-threaded hollow stem,0. a 5 v l' Said stem C is arrangedlongitudinally within a cap, D, which is screwed into thev topl of the outer .box A, and it is provided with a rotary, without a longitudinal motion, so that by turning the same the valveplug B B' maybe raised from or lowered to the seat a.

The said' valve-plate B of the plug B B is made to conform loosely togthree sides, or rather to the top and bottom and one side ofthe wedge B of the said plug, so as to allow `a limited longitudinal movement of the wedge independently thereof, and is connected thereto by the passing of the stem b through a slot, s, in its upper side, and a pin', o, through a slot in its lower side.

Said slots are made Ito fit loosely around thesaid stem and pin, so as to allow a limited lateral play to the said valve-plate B. Y v y Coiled around the stem b, between the upper side 0r top of thisv valve-plate lB and a collar, c,on the stem, is a spiral spring, e, for the purpose of holding ythe said valve-plate against the but 'of the wedge, thereby preventing shaking of the parts when Vthe valve is open, and also so that the valve may be used in an inverted or other position, when desirable.

The rotary stem C is provided, at its bottom, with` a circular flange, or head d,.fltted and ground into the dome of the cap D, so that the upward pressure of the steam against its under side willlca'use its closer fitting to the dome, for vthe purpose of preventing leakage, and thereby 4obviate ,the necessity of vusing packing. N

This iiange, or head d, is held against the said dome, l when not acted upon by the steam, by means of a spiral spring, g, arranged between the upper extremity of the cap D and a collar, f, en the said stem O. v

Provision is made for dressing and trning the seat a, andthe dat surfaces of the square, or quadrangular chamber E, by means of an opening made through the box A, and directly under the. bottom of the said chamber E and seat a. Said opening is afterward closed with a screw-cap, Ao. f `I The operation of this valve is such that when the stem O is turned, the valve-,plug B B is carried up or down, according as the stem is turned backward or forward, the back -or straight side of the wedge B sliding against the perpendicular surface of the wall of the chamber E y Upon turning the stem in such manner as to lower the plug, the valve-plate B will seat itself upon the seat a, and at the same time rest its lower end upon the bottom of the chamber E, whereupon a continued' turning of the said stein C will cause the wedge B', in passing still further downward, while the said plate remains stationary, to wedge the said plate more tightly against the seat a, thereby eiectuallyshutting oii the steam.

What I claim as my invention, anddesire to have secured by Letters Patent, isl I The valve-plug B B, consisting of the valve-plate B, and the wedge Bwhereby the plug, when seated,

vis expanded by the downward movement of the wedge, y

substantially as herein described. y

. Y BENIN. GREEN MARTIN.

Witnesses: g

FRED. HAYNES, J. W. Oooius. 

